| /* |
| * copyright (c) 2001 Fabrice Bellard |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| #ifndef AVFORMAT_AVIO_H |
| #define AVFORMAT_AVIO_H |
| |
| /** |
| * @file |
| * @ingroup lavf_io |
| * Buffered I/O operations |
| */ |
| |
| #include <stdint.h> |
| |
| #include "libavutil/common.h" |
| #include "libavutil/dict.h" |
| #include "libavutil/log.h" |
| |
| #include "libavformat/version.h" |
| |
| /** |
| * Seeking works like for a local file. |
| */ |
| #define AVIO_SEEKABLE_NORMAL (1 << 0) |
| |
| /** |
| * Seeking by timestamp with avio_seek_time() is possible. |
| */ |
| #define AVIO_SEEKABLE_TIME (1 << 1) |
| |
| /** |
| * Callback for checking whether to abort blocking functions. |
| * AVERROR_EXIT is returned in this case by the interrupted |
| * function. During blocking operations, callback is called with |
| * opaque as parameter. If the callback returns 1, the |
| * blocking operation will be aborted. |
| * |
| * No members can be added to this struct without a major bump, if |
| * new elements have been added after this struct in AVFormatContext |
| * or AVIOContext. |
| */ |
| typedef struct AVIOInterruptCB { |
| int (*callback)(void*); |
| void *opaque; |
| } AVIOInterruptCB; |
| |
| /** |
| * Directory entry types. |
| */ |
| enum AVIODirEntryType { |
| AVIO_ENTRY_UNKNOWN, |
| AVIO_ENTRY_BLOCK_DEVICE, |
| AVIO_ENTRY_CHARACTER_DEVICE, |
| AVIO_ENTRY_DIRECTORY, |
| AVIO_ENTRY_NAMED_PIPE, |
| AVIO_ENTRY_SYMBOLIC_LINK, |
| AVIO_ENTRY_SOCKET, |
| AVIO_ENTRY_FILE, |
| AVIO_ENTRY_SERVER, |
| AVIO_ENTRY_SHARE, |
| AVIO_ENTRY_WORKGROUP, |
| }; |
| |
| /** |
| * Describes single entry of the directory. |
| * |
| * Only name and type fields are guaranteed be set. |
| * Rest of fields are protocol or/and platform dependent and might be unknown. |
| */ |
| typedef struct AVIODirEntry { |
| char *name; /**< Filename */ |
| int type; /**< Type of the entry */ |
| int utf8; /**< Set to 1 when name is encoded with UTF-8, 0 otherwise. |
| Name can be encoded with UTF-8 even though 0 is set. */ |
| int64_t size; /**< File size in bytes, -1 if unknown. */ |
| int64_t modification_timestamp; /**< Time of last modification in microseconds since unix |
| epoch, -1 if unknown. */ |
| int64_t access_timestamp; /**< Time of last access in microseconds since unix epoch, |
| -1 if unknown. */ |
| int64_t status_change_timestamp; /**< Time of last status change in microseconds since unix |
| epoch, -1 if unknown. */ |
| int64_t user_id; /**< User ID of owner, -1 if unknown. */ |
| int64_t group_id; /**< Group ID of owner, -1 if unknown. */ |
| int64_t filemode; /**< Unix file mode, -1 if unknown. */ |
| } AVIODirEntry; |
| |
| typedef struct AVIODirContext { |
| struct URLContext *url_context; |
| } AVIODirContext; |
| |
| /** |
| * Different data types that can be returned via the AVIO |
| * write_data_type callback. |
| */ |
| enum AVIODataMarkerType { |
| /** |
| * Header data; this needs to be present for the stream to be decodeable. |
| */ |
| AVIO_DATA_MARKER_HEADER, |
| /** |
| * A point in the output bytestream where a decoder can start decoding |
| * (i.e. a keyframe). A demuxer/decoder given the data flagged with |
| * AVIO_DATA_MARKER_HEADER, followed by any AVIO_DATA_MARKER_SYNC_POINT, |
| * should give decodeable results. |
| */ |
| AVIO_DATA_MARKER_SYNC_POINT, |
| /** |
| * A point in the output bytestream where a demuxer can start parsing |
| * (for non self synchronizing bytestream formats). That is, any |
| * non-keyframe packet start point. |
| */ |
| AVIO_DATA_MARKER_BOUNDARY_POINT, |
| /** |
| * This is any, unlabelled data. It can either be a muxer not marking |
| * any positions at all, it can be an actual boundary/sync point |
| * that the muxer chooses not to mark, or a later part of a packet/fragment |
| * that is cut into multiple write callbacks due to limited IO buffer size. |
| */ |
| AVIO_DATA_MARKER_UNKNOWN, |
| /** |
| * Trailer data, which doesn't contain actual content, but only for |
| * finalizing the output file. |
| */ |
| AVIO_DATA_MARKER_TRAILER, |
| /** |
| * A point in the output bytestream where the underlying AVIOContext might |
| * flush the buffer depending on latency or buffering requirements. Typically |
| * means the end of a packet. |
| */ |
| AVIO_DATA_MARKER_FLUSH_POINT, |
| }; |
| |
| /** |
| * Bytestream IO Context. |
| * New fields can be added to the end with minor version bumps. |
| * Removal, reordering and changes to existing fields require a major |
| * version bump. |
| * sizeof(AVIOContext) must not be used outside libav*. |
| * |
| * @note None of the function pointers in AVIOContext should be called |
| * directly, they should only be set by the client application |
| * when implementing custom I/O. Normally these are set to the |
| * function pointers specified in avio_alloc_context() |
| */ |
| typedef struct AVIOContext { |
| /** |
| * A class for private options. |
| * |
| * If this AVIOContext is created by avio_open2(), av_class is set and |
| * passes the options down to protocols. |
| * |
| * If this AVIOContext is manually allocated, then av_class may be set by |
| * the caller. |
| * |
| * warning -- this field can be NULL, be sure to not pass this AVIOContext |
| * to any av_opt_* functions in that case. |
| */ |
| const AVClass *av_class; |
| |
| /* |
| * The following shows the relationship between buffer, buf_ptr, |
| * buf_ptr_max, buf_end, buf_size, and pos, when reading and when writing |
| * (since AVIOContext is used for both): |
| * |
| ********************************************************************************** |
| * READING |
| ********************************************************************************** |
| * |
| * | buffer_size | |
| * |---------------------------------------| |
| * | | |
| * |
| * buffer buf_ptr buf_end |
| * +---------------+-----------------------+ |
| * |/ / / / / / / /|/ / / / / / /| | |
| * read buffer: |/ / consumed / | to be read /| | |
| * |/ / / / / / / /|/ / / / / / /| | |
| * +---------------+-----------------------+ |
| * |
| * pos |
| * +-------------------------------------------+-----------------+ |
| * input file: | | | |
| * +-------------------------------------------+-----------------+ |
| * |
| * |
| ********************************************************************************** |
| * WRITING |
| ********************************************************************************** |
| * |
| * | buffer_size | |
| * |--------------------------------------| |
| * | | |
| * |
| * buf_ptr_max |
| * buffer (buf_ptr) buf_end |
| * +-----------------------+--------------+ |
| * |/ / / / / / / / / / / /| | |
| * write buffer: | / / to be flushed / / | | |
| * |/ / / / / / / / / / / /| | |
| * +-----------------------+--------------+ |
| * buf_ptr can be in this |
| * due to a backward seek |
| * |
| * pos |
| * +-------------+----------------------------------------------+ |
| * output file: | | | |
| * +-------------+----------------------------------------------+ |
| * |
| */ |
| unsigned char *buffer; /**< Start of the buffer. */ |
| int buffer_size; /**< Maximum buffer size */ |
| unsigned char *buf_ptr; /**< Current position in the buffer */ |
| unsigned char *buf_end; /**< End of the data, may be less than |
| buffer+buffer_size if the read function returned |
| less data than requested, e.g. for streams where |
| no more data has been received yet. */ |
| void *opaque; /**< A private pointer, passed to the read/write/seek/... |
| functions. */ |
| int (*read_packet)(void *opaque, uint8_t *buf, int buf_size); |
| int (*write_packet)(void *opaque, uint8_t *buf, int buf_size); |
| int64_t (*seek)(void *opaque, int64_t offset, int whence); |
| int64_t pos; /**< position in the file of the current buffer */ |
| int must_flush; /**< unused */ |
| int eof_reached; /**< true if eof reached */ |
| int write_flag; /**< true if open for writing */ |
| int max_packet_size; |
| unsigned long checksum; |
| unsigned char *checksum_ptr; |
| unsigned long (*update_checksum)(unsigned long checksum, const uint8_t *buf, unsigned int size); |
| int error; /**< contains the error code or 0 if no error happened */ |
| /** |
| * Pause or resume playback for network streaming protocols - e.g. MMS. |
| */ |
| int (*read_pause)(void *opaque, int pause); |
| /** |
| * Seek to a given timestamp in stream with the specified stream_index. |
| * Needed for some network streaming protocols which don't support seeking |
| * to byte position. |
| */ |
| int64_t (*read_seek)(void *opaque, int stream_index, |
| int64_t timestamp, int flags); |
| /** |
| * A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable. |
| */ |
| int seekable; |
| |
| /** |
| * max filesize, used to limit allocations |
| * This field is internal to libavformat and access from outside is not allowed. |
| */ |
| int64_t maxsize; |
| |
| /** |
| * avio_read and avio_write should if possible be satisfied directly |
| * instead of going through a buffer, and avio_seek will always |
| * call the underlying seek function directly. |
| */ |
| int direct; |
| |
| /** |
| * Bytes read statistic |
| * This field is internal to libavformat and access from outside is not allowed. |
| */ |
| int64_t bytes_read; |
| |
| /** |
| * seek statistic |
| * This field is internal to libavformat and access from outside is not allowed. |
| */ |
| int seek_count; |
| |
| /** |
| * writeout statistic |
| * This field is internal to libavformat and access from outside is not allowed. |
| */ |
| int writeout_count; |
| |
| /** |
| * Original buffer size |
| * used internally after probing and ensure seekback to reset the buffer size |
| * This field is internal to libavformat and access from outside is not allowed. |
| */ |
| int orig_buffer_size; |
| |
| /** |
| * Threshold to favor readahead over seek. |
| * This is current internal only, do not use from outside. |
| */ |
| int short_seek_threshold; |
| |
| /** |
| * ',' separated list of allowed protocols. |
| */ |
| const char *protocol_whitelist; |
| |
| /** |
| * ',' separated list of disallowed protocols. |
| */ |
| const char *protocol_blacklist; |
| |
| /** |
| * A callback that is used instead of write_packet. |
| */ |
| int (*write_data_type)(void *opaque, uint8_t *buf, int buf_size, |
| enum AVIODataMarkerType type, int64_t time); |
| /** |
| * If set, don't call write_data_type separately for AVIO_DATA_MARKER_BOUNDARY_POINT, |
| * but ignore them and treat them as AVIO_DATA_MARKER_UNKNOWN (to avoid needlessly |
| * small chunks of data returned from the callback). |
| */ |
| int ignore_boundary_point; |
| |
| /** |
| * Internal, not meant to be used from outside of AVIOContext. |
| */ |
| enum AVIODataMarkerType current_type; |
| int64_t last_time; |
| |
| /** |
| * A callback that is used instead of short_seek_threshold. |
| * This is current internal only, do not use from outside. |
| */ |
| int (*short_seek_get)(void *opaque); |
| |
| int64_t written; |
| |
| /** |
| * Maximum reached position before a backward seek in the write buffer, |
| * used keeping track of already written data for a later flush. |
| */ |
| unsigned char *buf_ptr_max; |
| |
| /** |
| * Try to buffer at least this amount of data before flushing it |
| */ |
| int min_packet_size; |
| } AVIOContext; |
| |
| /** |
| * Return the name of the protocol that will handle the passed URL. |
| * |
| * NULL is returned if no protocol could be found for the given URL. |
| * |
| * @return Name of the protocol or NULL. |
| */ |
| const char *avio_find_protocol_name(const char *url); |
| |
| /** |
| * Return AVIO_FLAG_* access flags corresponding to the access permissions |
| * of the resource in url, or a negative value corresponding to an |
| * AVERROR code in case of failure. The returned access flags are |
| * masked by the value in flags. |
| * |
| * @note This function is intrinsically unsafe, in the sense that the |
| * checked resource may change its existence or permission status from |
| * one call to another. Thus you should not trust the returned value, |
| * unless you are sure that no other processes are accessing the |
| * checked resource. |
| */ |
| int avio_check(const char *url, int flags); |
| |
| /** |
| * Move or rename a resource. |
| * |
| * @note url_src and url_dst should share the same protocol and authority. |
| * |
| * @param url_src url to resource to be moved |
| * @param url_dst new url to resource if the operation succeeded |
| * @return >=0 on success or negative on error. |
| */ |
| int avpriv_io_move(const char *url_src, const char *url_dst); |
| |
| /** |
| * Delete a resource. |
| * |
| * @param url resource to be deleted. |
| * @return >=0 on success or negative on error. |
| */ |
| int avpriv_io_delete(const char *url); |
| |
| /** |
| * Open directory for reading. |
| * |
| * @param s directory read context. Pointer to a NULL pointer must be passed. |
| * @param url directory to be listed. |
| * @param options A dictionary filled with protocol-private options. On return |
| * this parameter will be destroyed and replaced with a dictionary |
| * containing options that were not found. May be NULL. |
| * @return >=0 on success or negative on error. |
| */ |
| int avio_open_dir(AVIODirContext **s, const char *url, AVDictionary **options); |
| |
| /** |
| * Get next directory entry. |
| * |
| * Returned entry must be freed with avio_free_directory_entry(). In particular |
| * it may outlive AVIODirContext. |
| * |
| * @param s directory read context. |
| * @param[out] next next entry or NULL when no more entries. |
| * @return >=0 on success or negative on error. End of list is not considered an |
| * error. |
| */ |
| int avio_read_dir(AVIODirContext *s, AVIODirEntry **next); |
| |
| /** |
| * Close directory. |
| * |
| * @note Entries created using avio_read_dir() are not deleted and must be |
| * freeded with avio_free_directory_entry(). |
| * |
| * @param s directory read context. |
| * @return >=0 on success or negative on error. |
| */ |
| int avio_close_dir(AVIODirContext **s); |
| |
| /** |
| * Free entry allocated by avio_read_dir(). |
| * |
| * @param entry entry to be freed. |
| */ |
| void avio_free_directory_entry(AVIODirEntry **entry); |
| |
| /** |
| * Allocate and initialize an AVIOContext for buffered I/O. It must be later |
| * freed with avio_context_free(). |
| * |
| * @param buffer Memory block for input/output operations via AVIOContext. |
| * The buffer must be allocated with av_malloc() and friends. |
| * It may be freed and replaced with a new buffer by libavformat. |
| * AVIOContext.buffer holds the buffer currently in use, |
| * which must be later freed with av_free(). |
| * @param buffer_size The buffer size is very important for performance. |
| * For protocols with fixed blocksize it should be set to this blocksize. |
| * For others a typical size is a cache page, e.g. 4kb. |
| * @param write_flag Set to 1 if the buffer should be writable, 0 otherwise. |
| * @param opaque An opaque pointer to user-specific data. |
| * @param read_packet A function for refilling the buffer, may be NULL. |
| * @param write_packet A function for writing the buffer contents, may be NULL. |
| * The function may not change the input buffers content. |
| * @param seek A function for seeking to specified byte position, may be NULL. |
| * |
| * @return Allocated AVIOContext or NULL on failure. |
| */ |
| AVIOContext *avio_alloc_context( |
| unsigned char *buffer, |
| int buffer_size, |
| int write_flag, |
| void *opaque, |
| int (*read_packet)(void *opaque, uint8_t *buf, int buf_size), |
| int (*write_packet)(void *opaque, uint8_t *buf, int buf_size), |
| int64_t (*seek)(void *opaque, int64_t offset, int whence)); |
| |
| /** |
| * Free the supplied IO context and everything associated with it. |
| * |
| * @param s Double pointer to the IO context. This function will write NULL |
| * into s. |
| */ |
| void avio_context_free(AVIOContext **s); |
| |
| void avio_w8(AVIOContext *s, int b); |
| void avio_write(AVIOContext *s, const unsigned char *buf, int size); |
| void avio_wl64(AVIOContext *s, uint64_t val); |
| void avio_wb64(AVIOContext *s, uint64_t val); |
| void avio_wl32(AVIOContext *s, unsigned int val); |
| void avio_wb32(AVIOContext *s, unsigned int val); |
| void avio_wl24(AVIOContext *s, unsigned int val); |
| void avio_wb24(AVIOContext *s, unsigned int val); |
| void avio_wl16(AVIOContext *s, unsigned int val); |
| void avio_wb16(AVIOContext *s, unsigned int val); |
| |
| /** |
| * Write a NULL-terminated string. |
| * @return number of bytes written. |
| */ |
| int avio_put_str(AVIOContext *s, const char *str); |
| |
| /** |
| * Convert an UTF-8 string to UTF-16LE and write it. |
| * @param s the AVIOContext |
| * @param str NULL-terminated UTF-8 string |
| * |
| * @return number of bytes written. |
| */ |
| int avio_put_str16le(AVIOContext *s, const char *str); |
| |
| /** |
| * Convert an UTF-8 string to UTF-16BE and write it. |
| * @param s the AVIOContext |
| * @param str NULL-terminated UTF-8 string |
| * |
| * @return number of bytes written. |
| */ |
| int avio_put_str16be(AVIOContext *s, const char *str); |
| |
| /** |
| * Mark the written bytestream as a specific type. |
| * |
| * Zero-length ranges are omitted from the output. |
| * |
| * @param time the stream time the current bytestream pos corresponds to |
| * (in AV_TIME_BASE units), or AV_NOPTS_VALUE if unknown or not |
| * applicable |
| * @param type the kind of data written starting at the current pos |
| */ |
| void avio_write_marker(AVIOContext *s, int64_t time, enum AVIODataMarkerType type); |
| |
| /** |
| * ORing this as the "whence" parameter to a seek function causes it to |
| * return the filesize without seeking anywhere. Supporting this is optional. |
| * If it is not supported then the seek function will return <0. |
| */ |
| #define AVSEEK_SIZE 0x10000 |
| |
| /** |
| * Passing this flag as the "whence" parameter to a seek function causes it to |
| * seek by any means (like reopening and linear reading) or other normally unreasonable |
| * means that can be extremely slow. |
| * This may be ignored by the seek code. |
| */ |
| #define AVSEEK_FORCE 0x20000 |
| |
| /** |
| * fseek() equivalent for AVIOContext. |
| * @return new position or AVERROR. |
| */ |
| int64_t avio_seek(AVIOContext *s, int64_t offset, int whence); |
| |
| /** |
| * Skip given number of bytes forward |
| * @return new position or AVERROR. |
| */ |
| int64_t avio_skip(AVIOContext *s, int64_t offset); |
| |
| /** |
| * ftell() equivalent for AVIOContext. |
| * @return position or AVERROR. |
| */ |
| static av_always_inline int64_t avio_tell(AVIOContext *s) |
| { |
| return avio_seek(s, 0, SEEK_CUR); |
| } |
| |
| /** |
| * Get the filesize. |
| * @return filesize or AVERROR |
| */ |
| int64_t avio_size(AVIOContext *s); |
| |
| /** |
| * feof() equivalent for AVIOContext. |
| * @return non zero if and only if end of file |
| */ |
| int avio_feof(AVIOContext *s); |
| #if FF_API_URL_FEOF |
| /** |
| * @deprecated use avio_feof() |
| */ |
| attribute_deprecated |
| int url_feof(AVIOContext *s); |
| #endif |
| |
| /** @warning Writes up to 4 KiB per call */ |
| int avio_printf(AVIOContext *s, const char *fmt, ...) av_printf_format(2, 3); |
| |
| /** |
| * Force flushing of buffered data. |
| * |
| * For write streams, force the buffered data to be immediately written to the output, |
| * without to wait to fill the internal buffer. |
| * |
| * For read streams, discard all currently buffered data, and advance the |
| * reported file position to that of the underlying stream. This does not |
| * read new data, and does not perform any seeks. |
| */ |
| void avio_flush(AVIOContext *s); |
| |
| /** |
| * Read size bytes from AVIOContext into buf. |
| * @return number of bytes read or AVERROR |
| */ |
| int avio_read(AVIOContext *s, unsigned char *buf, int size); |
| |
| /** |
| * Read size bytes from AVIOContext into buf. Unlike avio_read(), this is allowed |
| * to read fewer bytes than requested. The missing bytes can be read in the next |
| * call. This always tries to read at least 1 byte. |
| * Useful to reduce latency in certain cases. |
| * @return number of bytes read or AVERROR |
| */ |
| int avio_read_partial(AVIOContext *s, unsigned char *buf, int size); |
| |
| /** |
| * @name Functions for reading from AVIOContext |
| * @{ |
| * |
| * @note return 0 if EOF, so you cannot use it if EOF handling is |
| * necessary |
| */ |
| int avio_r8 (AVIOContext *s); |
| unsigned int avio_rl16(AVIOContext *s); |
| unsigned int avio_rl24(AVIOContext *s); |
| unsigned int avio_rl32(AVIOContext *s); |
| uint64_t avio_rl64(AVIOContext *s); |
| unsigned int avio_rb16(AVIOContext *s); |
| unsigned int avio_rb24(AVIOContext *s); |
| unsigned int avio_rb32(AVIOContext *s); |
| uint64_t avio_rb64(AVIOContext *s); |
| /** |
| * @} |
| */ |
| |
| /** |
| * Read a string from pb into buf. The reading will terminate when either |
| * a NULL character was encountered, maxlen bytes have been read, or nothing |
| * more can be read from pb. The result is guaranteed to be NULL-terminated, it |
| * will be truncated if buf is too small. |
| * Note that the string is not interpreted or validated in any way, it |
| * might get truncated in the middle of a sequence for multi-byte encodings. |
| * |
| * @return number of bytes read (is always <= maxlen). |
| * If reading ends on EOF or error, the return value will be one more than |
| * bytes actually read. |
| */ |
| int avio_get_str(AVIOContext *pb, int maxlen, char *buf, int buflen); |
| |
| /** |
| * Read a UTF-16 string from pb and convert it to UTF-8. |
| * The reading will terminate when either a null or invalid character was |
| * encountered or maxlen bytes have been read. |
| * @return number of bytes read (is always <= maxlen) |
| */ |
| int avio_get_str16le(AVIOContext *pb, int maxlen, char *buf, int buflen); |
| int avio_get_str16be(AVIOContext *pb, int maxlen, char *buf, int buflen); |
| |
| |
| /** |
| * @name URL open modes |
| * The flags argument to avio_open must be one of the following |
| * constants, optionally ORed with other flags. |
| * @{ |
| */ |
| #define AVIO_FLAG_READ 1 /**< read-only */ |
| #define AVIO_FLAG_WRITE 2 /**< write-only */ |
| #define AVIO_FLAG_READ_WRITE (AVIO_FLAG_READ|AVIO_FLAG_WRITE) /**< read-write pseudo flag */ |
| /** |
| * @} |
| */ |
| |
| /** |
| * Use non-blocking mode. |
| * If this flag is set, operations on the context will return |
| * AVERROR(EAGAIN) if they can not be performed immediately. |
| * If this flag is not set, operations on the context will never return |
| * AVERROR(EAGAIN). |
| * Note that this flag does not affect the opening/connecting of the |
| * context. Connecting a protocol will always block if necessary (e.g. on |
| * network protocols) but never hang (e.g. on busy devices). |
| * Warning: non-blocking protocols is work-in-progress; this flag may be |
| * silently ignored. |
| */ |
| #define AVIO_FLAG_NONBLOCK 8 |
| |
| /** |
| * Use direct mode. |
| * avio_read and avio_write should if possible be satisfied directly |
| * instead of going through a buffer, and avio_seek will always |
| * call the underlying seek function directly. |
| */ |
| #define AVIO_FLAG_DIRECT 0x8000 |
| |
| /** |
| * Create and initialize a AVIOContext for accessing the |
| * resource indicated by url. |
| * @note When the resource indicated by url has been opened in |
| * read+write mode, the AVIOContext can be used only for writing. |
| * |
| * @param s Used to return the pointer to the created AVIOContext. |
| * In case of failure the pointed to value is set to NULL. |
| * @param url resource to access |
| * @param flags flags which control how the resource indicated by url |
| * is to be opened |
| * @return >= 0 in case of success, a negative value corresponding to an |
| * AVERROR code in case of failure |
| */ |
| int avio_open(AVIOContext **s, const char *url, int flags); |
| |
| /** |
| * Create and initialize a AVIOContext for accessing the |
| * resource indicated by url. |
| * @note When the resource indicated by url has been opened in |
| * read+write mode, the AVIOContext can be used only for writing. |
| * |
| * @param s Used to return the pointer to the created AVIOContext. |
| * In case of failure the pointed to value is set to NULL. |
| * @param url resource to access |
| * @param flags flags which control how the resource indicated by url |
| * is to be opened |
| * @param int_cb an interrupt callback to be used at the protocols level |
| * @param options A dictionary filled with protocol-private options. On return |
| * this parameter will be destroyed and replaced with a dict containing options |
| * that were not found. May be NULL. |
| * @return >= 0 in case of success, a negative value corresponding to an |
| * AVERROR code in case of failure |
| */ |
| int avio_open2(AVIOContext **s, const char *url, int flags, |
| const AVIOInterruptCB *int_cb, AVDictionary **options); |
| |
| /** |
| * Close the resource accessed by the AVIOContext s and free it. |
| * This function can only be used if s was opened by avio_open(). |
| * |
| * The internal buffer is automatically flushed before closing the |
| * resource. |
| * |
| * @return 0 on success, an AVERROR < 0 on error. |
| * @see avio_closep |
| */ |
| int avio_close(AVIOContext *s); |
| |
| /** |
| * Close the resource accessed by the AVIOContext *s, free it |
| * and set the pointer pointing to it to NULL. |
| * This function can only be used if s was opened by avio_open(). |
| * |
| * The internal buffer is automatically flushed before closing the |
| * resource. |
| * |
| * @return 0 on success, an AVERROR < 0 on error. |
| * @see avio_close |
| */ |
| int avio_closep(AVIOContext **s); |
| |
| |
| /** |
| * Open a write only memory stream. |
| * |
| * @param s new IO context |
| * @return zero if no error. |
| */ |
| int avio_open_dyn_buf(AVIOContext **s); |
| |
| /** |
| * Return the written size and a pointer to the buffer. |
| * The AVIOContext stream is left intact. |
| * The buffer must NOT be freed. |
| * No padding is added to the buffer. |
| * |
| * @param s IO context |
| * @param pbuffer pointer to a byte buffer |
| * @return the length of the byte buffer |
| */ |
| int avio_get_dyn_buf(AVIOContext *s, uint8_t **pbuffer); |
| |
| /** |
| * Return the written size and a pointer to the buffer. The buffer |
| * must be freed with av_free(). |
| * Padding of AV_INPUT_BUFFER_PADDING_SIZE is added to the buffer. |
| * |
| * @param s IO context |
| * @param pbuffer pointer to a byte buffer |
| * @return the length of the byte buffer |
| */ |
| int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer); |
| |
| /** |
| * Iterate through names of available protocols. |
| * |
| * @param opaque A private pointer representing current protocol. |
| * It must be a pointer to NULL on first iteration and will |
| * be updated by successive calls to avio_enum_protocols. |
| * @param output If set to 1, iterate over output protocols, |
| * otherwise over input protocols. |
| * |
| * @return A static string containing the name of current protocol or NULL |
| */ |
| const char *avio_enum_protocols(void **opaque, int output); |
| |
| /** |
| * Pause and resume playing - only meaningful if using a network streaming |
| * protocol (e.g. MMS). |
| * |
| * @param h IO context from which to call the read_pause function pointer |
| * @param pause 1 for pause, 0 for resume |
| */ |
| int avio_pause(AVIOContext *h, int pause); |
| |
| /** |
| * Seek to a given timestamp relative to some component stream. |
| * Only meaningful if using a network streaming protocol (e.g. MMS.). |
| * |
| * @param h IO context from which to call the seek function pointers |
| * @param stream_index The stream index that the timestamp is relative to. |
| * If stream_index is (-1) the timestamp should be in AV_TIME_BASE |
| * units from the beginning of the presentation. |
| * If a stream_index >= 0 is used and the protocol does not support |
| * seeking based on component streams, the call will fail. |
| * @param timestamp timestamp in AVStream.time_base units |
| * or if there is no stream specified then in AV_TIME_BASE units. |
| * @param flags Optional combination of AVSEEK_FLAG_BACKWARD, AVSEEK_FLAG_BYTE |
| * and AVSEEK_FLAG_ANY. The protocol may silently ignore |
| * AVSEEK_FLAG_BACKWARD and AVSEEK_FLAG_ANY, but AVSEEK_FLAG_BYTE will |
| * fail if used and not supported. |
| * @return >= 0 on success |
| * @see AVInputFormat::read_seek |
| */ |
| int64_t avio_seek_time(AVIOContext *h, int stream_index, |
| int64_t timestamp, int flags); |
| |
| /* Avoid a warning. The header can not be included because it breaks c++. */ |
| struct AVBPrint; |
| |
| /** |
| * Read contents of h into print buffer, up to max_size bytes, or up to EOF. |
| * |
| * @return 0 for success (max_size bytes read or EOF reached), negative error |
| * code otherwise |
| */ |
| int avio_read_to_bprint(AVIOContext *h, struct AVBPrint *pb, size_t max_size); |
| |
| /** |
| * Accept and allocate a client context on a server context. |
| * @param s the server context |
| * @param c the client context, must be unallocated |
| * @return >= 0 on success or a negative value corresponding |
| * to an AVERROR on failure |
| */ |
| int avio_accept(AVIOContext *s, AVIOContext **c); |
| |
| /** |
| * Perform one step of the protocol handshake to accept a new client. |
| * This function must be called on a client returned by avio_accept() before |
| * using it as a read/write context. |
| * It is separate from avio_accept() because it may block. |
| * A step of the handshake is defined by places where the application may |
| * decide to change the proceedings. |
| * For example, on a protocol with a request header and a reply header, each |
| * one can constitute a step because the application may use the parameters |
| * from the request to change parameters in the reply; or each individual |
| * chunk of the request can constitute a step. |
| * If the handshake is already finished, avio_handshake() does nothing and |
| * returns 0 immediately. |
| * |
| * @param c the client context to perform the handshake on |
| * @return 0 on a complete and successful handshake |
| * > 0 if the handshake progressed, but is not complete |
| * < 0 for an AVERROR code |
| */ |
| int avio_handshake(AVIOContext *c); |
| #endif /* AVFORMAT_AVIO_H */ |
